1. Field of the Invention
The present invention relates to distributed computing environments, and more particularly to communication between various programs operating in the distributed computing environments.
2. Description of the Related Art
Recently, distributed computing environments have become widespread. Accordingly, extensive efforts have been made to facilitate communication between the various computing nodes which typically operate in such environments. One such effort is the development of the Simple Object Access Protocol (SOAP). SOAP is a standard which can be used to facilitate communication between different computing nodes operating in different platforms (or operating systems). As such, SOAP provides a way for a computing program (program) running in one kind of operating system (e.g., Windows 2000) to communicate with another computer program which is running in another kind of operating system (e.g., Linux).
Typically SOAP uses Extensible Markup Language (XML) and a transport protocol (such as HTTP, SMTP, MQ, etc.) as the mechanisms for information exchange. SOAP specifies how to encode an XML file so that a computer program running in one computer can call a computer program in another computer. This allows the computer program running in the first computer to send information to the program running in the other computer (e.g., one program to call another program). In addition, SOAP specifies how the called program can return a response. Since HTTP and XML Web protocols are usually installed and available for use in most operating platforms, SOAP provides a readily available solution to the difficult problem of allowing computer programs running in different environments to communicate with each other.
A major design goal for SOAP is simplicity and extensibility. This means that there are several features of traditional messaging systems and distributed object systems that are not part of the core SOAP specification. Accordingly, SOAP can be used as a lightweight protocol for exchange of information in a decentralized, distributed environment. As an XML based protocol, SOAP can consist of three parts: an envelope that defines a framework for describing what is in a message and how to process it, a set of encoding rules for expressing instances of application-defined data types, and a convention for representing remote procedure calls (RPC) and responses. The SOAP envelope construct defines an overall framework for expressing what is in a message, who should deal with it, and whether it is optional or mandatory. The SOAP encoding rules define a serialization mechanism that can be used to exchange instances of application-defined data types. The SOAP RPC representation defines a convention that can be used to represent remote procedure calls and responses. SOAP does not itself define any application semantics, such as a programming model or implementation specific semantics. Instead, it defines a simple mechanism for expressing application semantics by providing a modular packaging model and encoding mechanisms for encoding data within modules. This allows SOAP to be used in a large variety of systems. Accordingly, it highly desirable to provide a communication environment which can use SOAP or similar protocols.
Unfortunately, conventional approaches fail to solve many other problems associated with communication between computer programs in distributed computing environments. One such shortcoming is that the conventional approaches fail to provide a solution which can simultaneously and efficiently bridge the many disparate characteristics which typically exist between the nodes that make up a distributed computing environment. Even in cases where a solution can be provided to account for a particular type of difference (e.g., relating to security features) between various nodes, typically a costly and/or ad hoc approach is used. To illustrate, FIG. 1 depicts a conventional distributed computing environment 100. As shown in FIG. 1, several interfaces are implemented and maintained to facilitate communication between a few client and server programs.
Accordingly, conventional approaches do not provide a comprehensive approach to bridging these differences. This means that in order to facilitate communication between the numerous nodes and programming environments that typically make up a distributed computing environment, a tremendous amount of resources have to be deployed to painstakingly implement each desirable feature between each and every program on each and every node. The inefficiencies inherent in such an approach are manifest.
In view of the foregoing, improved techniques for allowing communication in distributed computing environments are needed.